It's pretty rare, but not unheard of. The opposite is a lot more common. Of course... it can take time for people to understand themselves, and most people are somewhere on the continuum. So, for example, one could be mostly gay, have a succession of same-sex relationships, perhaps even really long term ones, and then, later, find that one person of the opposite sex that they really connect with. I wouldn't get too worried about it. The label isn't important. Being true to yourself is
I never came out as a lesbian, but I thought I was most of my teens until realizing and accepting that I was bisexual many years later.
I came out as a lesbian in high school and dated exclusively girls. Then in college I met a guy and fell in love. I'm still much more attracted to women, but had to sort of admit I was Bi rather than gay both to myself, and people I know.
Sure, it can happen. Usually those who find someone of the opposite sex to like and question their sexuality all over again.
Yes! Me! I came out as a lesbian first and then realized I was bisexual last year. I dated women only in my early 20's and now I've been dating more men than women. Honestly, I don't think it's as rare as people think. I just think it's more taboo. I think it's generally more frowned upon for someone to go from gay to bi then vice versa because it gives the illusion that sexuality is a choice (when that's not the case at all!) I've seen quite a few stories on EC from people that came out as gay first and then realized they were bisexual. I still haven't fully come out as bisexual though. A lot of my friends still think I'm gay and I've had a hard time re-coming out but it is a work in progress. Being bisexual definitely has its own unique challenges that I'm still trying to figure out.